Robert Hargraves, professor of geosciences emeritus, dies

PRINCETON, N.J. -- Robert B. Hargraves, a member of the Princeton University
geosciences faculty from 1961 to his retirement in 1994, died March 21
at age 74 from viral pneumonia brought on by complications from radiation
and chemotherapy.

His family will host a gathering in his honor at Prospect House on the
Princeton campus on Friday, March 28, from 3 to 5 p.m.

Hargraves was internationally known for his broad concern with geologic
problems spanning the full 4.5 billion-year history of Earth, as well
as with the geology of other solar system bodies. The day before he entered
the hospital for his final visit, he was finishing up work on a previously
unanticipated type of rock magnetism with major implications for understanding
the geological history of Earth, Mars and the moon.

"All of us in the geosciences department had the highest regard
for Rob as a scientist and a colleague," said Anthony Dahlen, chair
of the department. "Through his broad geological perspective, he
made many important contributions to science, and we are saddened that
his career was tragically shortened."

The scope of his work goes back to the start of his career in South Africa,
where the gold and diamond resources allowed him to achieve insights to
the origins of some of Earth's oldest rocks.

Hargraves was born on Aug. 11, 1928, in Durban, Natal, South Africa,
of an American father and South African mother. He received a B.Sc. Hons
at Natal University College in geology and chemistry in 1948, and began
his professional career as a mining geologist in Africa. He moved to the
United States in 1952 to work for Newmont Mining Corp. and was subsequently
drafted for service in the U.S. Army. In 1955, during his service, he
married Sybil Sinclair, whom he had known in South Africa. Following his
discharge in 1956, he entered graduate school at Princeton.

At Princeton, Hargraves began to combine two important areas of geology:
petrology, the use of microscopes and other tools to study the grain-level
detail of rocks; and paleomagnetism, the study of how the Earth's magnetic
field left unique signatures in the structure of nascent rocks and how
this signature reflects the movement of continents. After receiving his
Ph.D. in 1959 from Princeton, Hargraves returned to South Africa, to the
University of the Witwatersrand. He joined the Princeton faculty in 1961.

During his long and fruitful career, he continued to combine studies
of rock magnetism and petrology to uncover the origins and history of
the rocks of the continental crust. His skill in making detailed studies
of individual rocks led him toward answering major questions of planetary
histories. His work took him and his students to many regions of North
America, Europe, South America, Africa and India.

His contributions to extraterrestrial geology began with his recognition
of geologic features near Vredefort, South Africa, and his early and controversial
proposal that they were caused by a meteor impact. More than 30 years
later, he recognized the same features in the so-called Beaverhead impact
feature in Montana and Idaho, and thus discovered one of the largest known
meteor impact sites on this planet. He was active in the petrologic analysis
of lunar samples from the Apollo landings, many of which resembled the
rocks he had studied for his Ph.D. work. He was principal investigator
for study of the magnetic properties of Martian rocks on the Viking landing
mission (1976) and on the Martian pathfinder mission (1999).

Hargraves' work frequently brought him into conflict with conventional
wisdom, said Robert Phinney, professor of geosciences. "He seemed
to thrive on the controversies. He liked to find opportunities to advance
science by questioning established ideas," Phinney said. "In
some cases it was mild skepticism or revisions, and in others he really
wanted to do it differently; he didn't get beaten down, he kept soldiering
on and made important contributions."

Hargraves wrote more than 100 articles in the geologic literature. Among
honors he received were the NASA Medal for Exceptional Scientific Achievement
in 1977 and the Jubilee Medal of the Geological Society of South Africa
in 1987. More information about Hargraves' work is available at http://geoweb.princeton.edu/people/faculty/emeritus/hargraves.html.

He is survived by his wife, Sybil, his daughters Monica Jane, Allison
Maude and Colleen Sinclair, and four grandchildren.